Thank you for the ask to answer.
You only need a medical exam to obtain a Canadian work visa if you have stayed in a certain country or territory prior to entering Canada, or will be working in the public health sector. See, the , and for more information.
However, your question is “why.” The answer is quite simple: disease control. When you come from a place that is known to have certain health problems, particularly contagious diseases, the public health interest needs to make sure you don’t come in and start making everyone sick. Imagine if a person outside of the country were a carrier of a disease and were asymptomatic, such as a Typhoid Mary — a person who seemed healthy but could make everyone sick simply by handling their food or medicine.
In order to protect the population as a whole and shut down any potential for an epidemic, these health examinations are required for anyone who will be living in the country for a significant period of time and could possibly do widespread damage to the population should they be a carrier of a disease.
But the examination is well worth it for many people! Happy Canada Day!
The medical information in this post is provided as an information resource only, and is not to be used or relied on for any diagnostic or treatment purposes. This information is not intended to be patient education, does not create any patient-physician relationship, and should not be used as a substitute for professional diagnosis and treatment.